We have no idea when AI aircraft reach the active runway, we only monitor the AI 'mode' flag which indicates if an AI aircraft is obtaining clearance, taxing, taking off, landing, going around, etc, etc. This is the most efficient method to monitor AI and make the various ATC calls on an 'after the event' basis. This is why you will not hear them handed off to Tower prior to takeoff. We also do not monitor AI traffic on their taxi route so would have no way of know if or when they were about to cross a runway and again there are no indications in the supplied 'Mode' flag to tell us that either. It is limited but probably 'nearly' the best we can do. I say 'nearly' as one day I do intend to revisit the AI monitoring process. You always have to remember though that PF3 does NOT control AI... that is done solely by the flight sim in use. Also, monitoring AI, especially at a busy airport, could potentially take a lot of processing time away from PF3's ATC procedures, especially those directed to you, so it has to be a fine balance. At this moment in time I think we have it balanced quite well.